1. Field of the Invention
The present invention relates to a wiring board that allows semiconductor devices and the like to be very densely mounted with high precision and that allows a package and module having excellent high-speed and reliability characteristics to be obtained, to a semiconductor device that uses the wiring board, and to a method of manufacturing the same.
2. Description of the Related Art
The semiconductor device described in Japanese Laid-open Patent Application No. 2001-345418 is an example of a conventional semiconductor device. In this publication, a two-sided mounted structure is disclosed in which semiconductor devices are placed by flip-chip mounting on the two sides of a circuit board. In accordance with the prior art, production yield and reliability can be improved by adjusting the glass transition temperature of the sealing resin that seals the mounted semiconductor devices.
However, in the prior art described above, the connection precision and quality tends to degrade due to the difference in the coefficient of thermal expansion between the substrate and the board of the semiconductor elements. For this reason, there are problems in that it is difficult to make very small wiring connections to the semiconductor elements, and the connection reliability is poor. It is therefore difficult to implement a large number of connections between chips having high wiring density by using this prior art.